On Thu, 4 Mar 2021 07:24:50 +0100
aitor <aitor_czr@???> wrote:

> Hi tito,
>
> On 4/3/21 0:47, tito via Dng wrote:
> > In my young years I used to tinker with linux distros on floppy
> > disks and there still where eth0, eth1 and so on but no udev,
> > so where did the names came from?
>
> They were assigned by the kernel, i think.
>
> Aitor.
>
>

Exactly, therefore udev only can modify the kernel assigned names,

How Linux assigns network interface names
The default name for Ethernet interfaces is based upon how Linux
initializes them during device discovery. As Linux finds the network
devices it will start numbering them starting with 0 and increasing
sequentially. Device discovery is dependent on the device driver load
order, PCI bus topology and the device driver code. On RHEL4, the
device driver load order is determined by the /etc/modprobe.conf file.
Device drivers assigned lower interface numbers in that file are loaded
first. On RHEL5 device drivers are loaded by thehotplug subsystem, i.e.
by udev, in parallel and it affects the assignment of names. When Linux
loads a single device driver it will initialize and find all devices
supported by that single driver first. On SLES, device drivers are
loaded based on the PCI bus topology as discovered by the kernel. The
PCI bus topology is composed of buses, bridges and devices. PCI devices
must be connected to a PCI bus. The PCI buses are connected by PCI
bridges to either other buses or to the system. The topology of the
system can be viewed as a tree. Using this analogy, the devices are
leaves, the system is the trunk, buses are branches and bridges exist
where branches meet each other or the trunk. Searching for PCI devices
in a system is accomplished by "walking the tree". The method of
walking the tree was modified in the 2.6 and later kernels, thus
changing the order in which devices are found. And last, each device
driver will search the PCI tree for all the devices it supports. Some
drivers have a list of different devices it will support and search the
tree for each device in the list. Other drivers will scan the tree and,
for each device, see if it is in its list of supported devices. This
will also change order of how devices are found and thus its interface
name. Changes in system configuration will also result in a different
enumeration order. If a new network card is inserted into a PCI slot,
its new position could be between two previous network devices. This
may result in the new card taking over the name of a previous card in
the system. The root cause of NIC enumeration mismatches is that there
is currently no industry standard to enable the OS to determine the
physical labeling of Ethernet ports on the motherboard.